Large Herbivorous Mammals: Exotic Species In Northern Australia By: W.J. Freeland

1
Large Herbivorous Mammals Exotic Species In
Northern AustraliaBy W.J. Freeland

• Reviewed By
• Joy Bryson Angela Maresco
• http//www.smallguide.com.au/maps/australia.gif

2
Purpose

• The purpose of this article is to examine the
  effects of mans deliberate introduction of
  large, herbivorous ungulates on their non-native
  environment of Northern Australian savannas.
• http//www.mareebaheritagecentre.com.au/images/Mt-
  Mulligan-landscape.jpg

3
Vocabulary Words

• Co-evolution- when 2 interdependent species adapt
  to one another
• Feral- wild untamed
• Inter-specific competition- when 2 or more
  species compete for the same resources
• Megafauna- large animals
• Pathogen- agents that cause disease
• Ungulates- hoofed mammals

4
The Problem

• Northern Australian savannas only have 6 large,
  herbivorous mammal species while Asian and
  African savannas have more
• Environmental changes developed
• Mans arrival to Australia probably is the cause

5
Effects of Europeans Arriving in Northern
Australia

• Extinction of large, herbivorous marsupials,
  flightless birds and lizard predators
• Possible climate changes
• Hunting
• Native habitat modification
• Due to fire
• Large ungulates from Europe, Asia and Africa were
  introduced

6
Herbivorous Mammals Quiz Directions Match the
scientific name of the following herbivorous
mammals with their picture

• Mus musculus
• Rattus exulans
• Orycytolagus cuniculus
• Sus scrofa
• Capra hircus
• Bos banteng
• Equus asinus
• Equus caballus
• Bubalus bubalis

a
i
h
b
f
e
c
d
g
7
Herbivorous Mammals Quiz Answers

• Mus musculus a
• Rattus exulans e
• Orycytolagus cuniculus d
• Sus scrofa g
• Capra hircus i
• Bos banteng h
• Equus asinus b
• Equus caballus f
• Bubalus bubalis c

a
i
h
b
f
e
c
d
g
8
Picture References

• http//genome.ucsc.edu/images/Mus_musculus.jpg
  mouse
• http//www.fieldmuseum.org/philippine_mammals/RODE
  NTIA/Muridae/RATTUS_exulans2.JPG rat
• http//fotoohota.spb.ru/members/mikhailov/02.jpg
  rabbit
• http//www.retamatour.com/web/02web/fauna/fichas/f
  otos/mamifer/Sus-scrofa.jpg Boar
• http//www.hilozoo.com/images/animals/m_goat.jpg
  goat
• http//www.csew.com/cattletag/Cattle20Website/Ima
  ges/banteng20flehmen.jpg ox
• http//www.roztocze.pl/zoo/img/Osiol1w.jpg ass
• http//www.ultimateungulate.com/Images/Equus_cabal
  lus/E_caballus3.jpg horse
• http//www.ultimateungulate.com/Images/Equus_cabal
  lus/E_caballus3.jpg buffalo

9
New Feral Species

• Spread throughout the region
• Bos taurus (cow)
• equus caballus (horse)
• Retained localized distribution
• Bos banteng (ox)
• Cervus unicolor (deer)
• Expanding ranges
• Camelus dromedarius (camel)

10
Predicted vs. Actual Densities of Herbivorous
Mammals

• Based on Damuth relationship
• Two surveys used
• Aerial
• Capture-Recapture

Table 35.1 The Human Impact Reader
11
Big is Beautiful But Lonely

• Illustrates concept of the Damuth relationship
• Density and body size are inversely related

http//www.sciencemag.org/cgi/content/full/289/548
4/1487/F1
12
Explanations for High Population Density

• Competition
• Predators
• Pathogens
• Plant Defenses
• All have a significant impact on herbivorous
  mammal population in the natural setting

13
Competition

• Influenced by the combination of species in a
  community (man-made or natural)
• Australian man-made communitys deficits compared
  to Asian/African natural communities
• Absence of time for co-evolutionmore competition
• Absence of large herbivoresimpossible to predict
• Absence of browsing speciesmore competition
• Influenced by biomass
• Biomass was found to be both inversely and
  directly related to inter-specific competition

14
Predators

• Low population of large predators
• Lack of predatorshigher density of introduced
  herbivores in Australia
• Dingo
• Consumed large species of herbivores
• Its effects cannot equate with that of species
  rich natural communities of predators with larger
  body sizes

http//www.thewildones.org/Gifs/dingo.gif
15
Pathogens

• Few native pathogens are capable of infecting the
  introduced species
• Few pathogens accompanied ungulates in Northern
  Australia compared to native herbivores
• Disease causes death in natural population of
  herbivorous mammals
• Less significant in feral herds

16
Plant Defenses

• Plants in Australia are similar to plants in
  other areas
• cause no harm to native or introduced species
  because of co- evolution

17
Possible Solution For Population Control

• Introduce pathogen
• Low cost
• Low environmental disturbance
• No human involvement
• No introduced predators

18
Summary

• Humans transported ungulates to Northern
  Australia and changed the environment
• There were undesirable changes in the
  environmental conditions for the native
  herbivores due to the deliberate introduction of
  feral ungulates into Northern Australia
• The introduced ungulates did not have natural
  factors to help control their population
• A solution is needed to control the feral
  ungulate population

19
Related StudyExtinctions of Herbivorous Mammals
in the Late Pleistocene of Australia in Relation
to their Feeding Ecology No Evidence for
Environmental Change as Cause of Extinction

• In this study, scientists tried to determine the
  cause of extinction of the megafauna species in
  Northern Australia. This article included
  information about the survival rate of browsers
  and grazers and how their body mass was related
  to their probability of extinction.
• http//www.ingentaconnect.com/content/bsc/aec/2004
  /00000029/00000005/art00007